摘要
目的 通过研究同位素内标物工作液浓度和保存时间对串联质谱法检测氨基酸含量的影响,在最大程度上消除内标对氨基酸测定的影响.方法 使用不同浓度（50,10,5,2.5,1.25,0.625 μmol/L）的同位素氨基酸内标液检测美国CDC提供的氨基酸定值质控纸片,通过分析比较相对偏倚,得到内标液最适工作浓度.按照最适浓度稀释内标液后,将其放置于4℃条件下4 h,1,7,10,14,21 d后,检测氨基酸定值质控纸片,通过分析比较实验批内不精密度,寻找到内标液的最长保存时间.结果 串联质谱法检测全血氨基酸的内标物最适工作液浓度为2.5 μmol/L,在此浓度下内标液在4℃条件下的最长稳定有效期是10 d.结论 同位素内标物作为串联质谱法检测氨基酸水平的标尺,在实验中起到至关重要的作用.对其最适的工作液浓度以及最长稳定有效期的探究,有助于对氨基酸测定的准确度和稳定性的把握.
Objective To find the methods to removal the influential factors of standards to detect amino acids in dry blood filter paper by analysing influence of daily working concentrations and conservation time of standards. Methods Amino acids in dry blood filter paper from CDC of USA were detected by tandem mass spectrometry with different daily working concentrations of standards （50,10,5,2.5,1.25 and 0. 625 μmol/L）. The optimal daily working concentrations of standards was got by calculating and comparing the bias in percent （bias%）. Amino acids were detected again by tandem mass spectrometry with different conservation time of standards （4 h, 1,7,10,14 d and 21 d）. The longest conservation time of standards was got by calculating and comparing within-run precision （CVthi %）. Results Optimal daily working concentrations of standards was 2.5 μmol/L. The longest conservation time of standards was 10 days. Conclusions The standards play an important role to detect amino acids in dry blood filter paper by tandem mass spectrometry. It is very necessary to explore the influence of daily working concentrations and conservation time of standards for detecting amino acids accurately.
出处
《现代检验医学杂志》
CAS
2010年第4期88-91,共4页
Journal of Modern Laboratory Medicine
关键词
内标
串联质谱法
干血滤纸片
氨基酸
standards
tandem mass spectrometry
dry blood filter paper
amino acids
